I disagree. The warlock class has typically been the one mana class that doesnt really worry about resource management. sure we had to tap in the past, but it was more of a survival gameplay skill then a mana management issue. "Am i going to survive if i tap right before the boss does a heavy AOE?" is not the same as a healers 'i need to make sure the tank survives, so i have to prioritize so much mana for emergencies and heal as much as i can other people in the meantime" or mages "If i run out of mana ill just stand here or use my mana regen abilities, but once they are on cooldown, im pretty much a dead stick floating in the toilet".

I've played my lock since day one, raided since molten core, and To be blatently honest, My mana has not been my problem. It's been my healers problem. Sure, you dont go stupid with it and drain resources you dont need to drain, but frankly its what makes the class so different ( and awesome)from mages or shadow priests. And Blizzard must agree or else they wouldnt have made Destruction so silly in terms of mana regen. Its a complete non issue for destruction. I could count on one hand the number of times while raiding destruction that ive actually run out of mana...it just comes too quickly for me to have a problem.

I remember back in vanilla WoW i encountered a warlock that insisted on putting spirit gear on his equipment. I tried to convince him he was being silly but he didnt listen.

While I agree, having something you hardly have to worry about is little fun, I'd even say annoying when it comes to Affliction and Demonology. Nowadays you don't even have to worry about Life Tapping, Soul Leech takes care of the whole "Is it safe to Life Tap" thing.
Life Tap is nothing more then: "Oh I'm low on Mana, lets press this button". It requires no thinking, you just do it whenever you need mana.

As for other casters, minus Arcane, mana isn't much of a problem either, however they do actually have to manage it with their cooldowns. If they screw up with their mana and cooldown management, everyone will notice it. If we go crazy with it, I doubt anyone will notice.

And while Mana doesn't have to go necessarily, I ask you, what's the point of still having Mana if you absolutely don't have to care about it. Wouldn't it be better to just get rid of it and replace it with something more interesting, or at least make changes to it so you actively have to manage it?

On the idea of replacing mana with something else. A neat idea for affliction would be to have 'Soul Shards' be used for utility/small burst purposes while making Affliction gather 'Soul Fragments' or maybe 'Lost Souls' for their main resource. Our DoTs will have a chance to generate them while Malefic Grasp will give a more guaranteed or more reliable source for them. I imagine the bar to have maybe 3-4 notches in it, signifying how much a 'Soul Spell' will cost. Each notch being a individual spell cast. One of the spells would of course be Haunt for our burst. We could save these souls for huge burst opportunities or cast them at more regular intervals for a steadier stream of damage. Then the other spell that would use this resource could be perhaps a healing spell or some type of survival spell. I just feel Affliction Warlocks should work alot more with souls than we currently do. Centering the spec around the gathering and use of souls would be neat I think.

Warlock PvP 2-piece set bonus no longer reduces cooldown on Unending Resolve and have been replaced by the former 4-piece set bonus where the Warlock's Twilight Ward absorbs damage from all magical schools.
Warlock PvP 4-piece set bonus now increases damage dealt by Agony, Corruption, Doom, Immolate, and Unstable Affliction by 10%.

p.s. need to include fel flame in pvp 4-piece bonus, or conflagrate

p.p.s. i dunno... new twilight ward in pvp abosrd only shadow and holy???

And while Mana doesn't have to go necessarily, I ask you, what's the point of still having Mana if you absolutely don't have to care about it. Wouldn't it be better to just get rid of it and replace it with something more interesting, or at least make changes to it so you actively have to manage it?

Warlocks have always been a class that didn't have to run out of mana, since we had an ability that let us regen whenever we wanted, the interesting part was juggling that with incoming raid damage and avoiding using the GCD during a burn phase / proc uptime. If the damage caused by lifetap is too negligible, then perhaps that's a problem with soul leech etc, not a problem with lifetap.

I'd personally be unhappy to see another of the most iconic warlock abilities going, losing shadowbolt from affliction was painful enough, though I wouldn't be opposed to seeing the old Dark Pact (draining mana from pet) returning, though that would probably require retooling pets, which isn't really worth doing to fix a problem that I can't say I agree exists.